Refrigeration apparatus



y 1943- G. D. HEISLER REFRIGERATION APPARATUS Filed May 6, 1941 2 Sheets-Sheet 1 hum/172w GLEN N D. HEISLER May 4, 1943. e. D. HEISLER REFRIGERATION APPARATUS Filed May 6, 1941 2 Sheets-Sheet 2 .//1a/a/7 70/ GLENN D. HEISLER 6M fl/ia/wey automatically and Patented May 4, 1943 UNITED STATES PATENT "o -neg 2,313,222 I Glenn D. Heisler, Portland, reg., assignor '-to Carbonic Control Corporation, Portland, Oreg.

Application-May 6, 1941, Serial No. 392,152 1 Claim. (CI. 13.2-91.5)

This invention relates to improvements in refrigeration apparatus. Its purpose is to provide a portable refrigeration unit free from pipes, secondary refrigerant, and ducts which can be operated from or by multiple sources of power thermostatically, and which is particularly well adapted for refrigerator trucks, freight cars, and the like where conservation of space is an important item. The unit includes an enclosed refrigerant chamber separated from an air tunnel by heat absorbing surfaces provided with fins and baffles to facilitate heat absorptionfrom the air within the air tunnel, and means to propel the air in a space being refrigerated through the air tunnel, thus providing an endless cycle ofcirculation within the compart- I ment under automatic control.

One of the principal objects of the invention is to provide air spaces along both sides of the refrigerant chamber for the purpose of pre-cooling air before it enters the air tunnel and to provide a space for collection of frost resulting from condensation of excess moisture in the air upon the sides of the refrigerant chamber and to provide an area of dead air for the purpose of insulation when air is not being circulated through the unit.

A further object is to provide an air tunnel and air passages, so that the loss in velocity and/or volume of air through the tunnel may be lessened. This involves changing the area of the surface of one of the passages to provide increased surface friction and modifying its shape in such a way so as to provide for an increase in pressure at the expense of velocity, in part, at any obstruction, such as a right angle turn in the passageway, and then by modifying the area again, principally by constriction, provide for an increase in velocity at the expense of pressure, in part.

A further object then is the provision of an absorption plate which will transmit a maximum amount of heat from a medium contacting one of its surfaces to a medium contacting its other surface which will provide a runway to guide the refrigerant when it is placed in the refrigerant chamber, and which will anchor the refrigerant within the compartment after it has been insulated, and which will so agitate churn, and retard the medium to be refrigerated that the maximum heat exchange will result, and which, by virtue of its design, will be economical and simple to construct.

A further object is the provision of an outlet for the air from the refrigerating cabinet to the space, or compartment beingrefrigerated'which will place the air in any part of the compartment in any manner desired, such as throwing a sheet of air over the entire area of the ceiling, so that the refrigerating action may be accomplished by natural circulation of air, namely, cool air down and warm air up, rather than by forcing air laterally through a load or space to be refrigerated.

A further object of the invention is the provision of apparatus of this character whichmay be used either to heat or chill air in a compartment without changing the construction of the apparatus or its mode of operation thus accomplished by utilizing the refrigerant chamber as a heat chamber by placing within it a heat producing liquid, or gas, in. a container that rests upon the runway guides of the absorption plate.

A still further object is the combination of two electric motors which enable the unit to operate on either commercial alternating current or on direct current from a battery, both of varying voltage. In construction, this feature consists of two electric motors of different circuits, connected either by flexible couplings, or over-riding clutch, and connected to a fan, or fans, for driving the air. To provide automatic control of these motors, a special electrical switch arrangement has been devised. The purpose of this switching mechanism is to enable the operator to change the source of electrical current without endangering the motors, and to operate only the motor intendedto operate on that circuit. This switching arrangement also includes a thermostatic control for either motor in operation.

The foregoing and other objects will appear as my invention is more fully hereinafter described in the following specification illustrated in the accompanying drawings and finally Figure 3 is a side elevation of a truck showing an access opening to the interior of the truck body and oneof several relative locations of my apparatus to the body.

Figure 4 is a sectional end elevation taken on the line 4-1 of Figure 2.

Figure 5 is a slightly enlarged sectional view taken on the line 5-5 of Figure 2.

Figure 6 is a sectional end elevation taken on 'material, such as copper, aluminum, or the like,

closed at one of its ends by an end wall 2 and provided wtih an access opening 3 at its opposite end, which is provided with a door 5. The top wall of the cabinet I, at the air-intake end, is formed with an opening 5 for open communication with the blower fan 6 mountedto the top wall of the cabinet, as shown, and which, by means of its shaft 1 and coupling 8, is driven by either one or the other of the alternating current or direct current motors, 9 and I, respectively, which are coupled together, as at H.

One side of the direct current motor I is "permanently connected by a circuit I2 with the battery circuit of a truck or other vehicle in which the apparatus may be installed. Any suitable manually actuated switch (not shown) may be disposed in this circuit, if desired. The wire l3 of the D. C. motor circuit I2 is one pole [3A of a two-pole double-throw magnetic switch A, and also with one pole I3B of another two-pole double-throw magnetic switch B, so that the direct current motor ID will only be energized when the magnetic switch B has been energized to close the contacts across the pole I3B, which completes the circuit from the source, over wire l3 into the motor In.

One side of the alternating current motor 9 is connected direct through wire M with a source of supply of 110 volts. The opposite side of the motor 9 is connected by wire 9A with the other pole of the two-pole double-throw magnetic switch A, and also with the other pole 9B of the double-switch A, and also,with the other pole 9B of the double-throw magnetic switch B, and thence back to the source. This 110 volt circuit preferably terminates in a plug for insertion in any convenient socket where 110 volt electricity is available; One side of the magnetic switch A is connected, as at [5, with the wire I with one side of a 110 volt line, and by wire IA with the opposite side of the line. Thus, any time current is directed through the 110 volt line, the

magnetic switch A will be energized to open the contacts across the one pole I 3A, and close the contacts across the other pole which connects the motor 9 on one side through wire M to one side of the source, and on the other side, through wire 9A up to the one pole 9B of the doublethrow magnetic switch B which, of course, will remain open so long as the magnetic switch B is de-energized.. The magnetic coil of the switch B is connected by circuit 1 6 with the circuit l2 supplying 12 volts. The circuit l6 embraces a thermostatic T disposed within a space, or compartment, to which the apparatus is applied, and controls the energization or de-energization of the coil B in accordance with'temperature COD? ditions. For example, on a rise of temperature,

connected with cabinet, and are sealed with walls of the refrigerant chamber, and the top the thermostat will close and energize the coil B to close the contacts across both poles 9B and 833 which, when the 110 volt circuit is broken by removal oft he plug, or otherwise,: will direct 12 volts from the circuit l2 through the pole 38, wire is, pole 53A, back to the source. When the 110 volt circuit is energized, and the thermostat closes the circuit 56, the contacts across the pole 93 will complete the circuit through wire 9A, then through the pole of the magnetic switch A and into the motor 9, thence through wire l4 back to the opposite side of the 110 volt circuit. By this arrangement, the 110 volt circuit may be completed, or broken, independently of the permanent connection of the circuit [2. Since the coil A can only be energized by co pleting the 110 volt circuit; and any time this circuit is not completed, the coil A is de-energized, which causes the pole MA to rest in a closed position to complete the 12 volt circuit to the motor l0, Disposed within the cabinet I is a refrigerant chamber i6A having its side, bottom, and both end walls arranged in spaced relation to the corresponding walls of the cabinet for the purpose of providing air spaces between the refrigerant chamber and the walls of the cabinet.

The bottom wall of the refrigerant chamber ridges, l1 and I8, respectively; and the sides of this bottom wall extend outwardly, as at l9 and 20, into sealed contact with the side walls of the cabinet to form an air tunnel 2| extending throughout the length of and sealed with respect to the refrigerant chamber. Disposed between the downwardly extending ridges l8 and between the outermost of said ridges and the side walls of the tunnel are a series of baiile plates 22 arranged in staggered relation. to each other to form a tortuous path of travel for the air' through the tunnel, which is drawn in through the fan 6 and forced down through the space 23 at the intake end of the cabinet. .Part of the incoming air, as indicated by arrows in Figures 2 and 6, is

.directed into the spaces between th side walls of therefrigerant chamber, and the walls of the cabinet above the flanges, l9 and 20. These air spaces terminate at vertical partitions, or bulkheads, 24 arranged near the forward end of the respect to the side wall of the cabinet, and theflanges, l9 and 20. These spaces provide air chambers surrounding the refrigerant chamber for thep pose of precooling the air before it enters the air tunnel, and to provide a space for collection of frost resulting from condensation of excess moisture in the air upon the sides of the refrigerant chamber, and to also provide an area of dead air for the purpose of insulation when air is not being circulated through the unit. The forward end of the tunnel is in open communication with a space 25 between the end of the refrigerant chamber and the end of the cabinet. Across the top and bottom corner of this space, I provide baflie plates 26 directed toward inwardly inclined surfaces 21 of the door 4. The purpose of this arrangement is to provide a passageway for the outgoing air so ment changes the area of the duct surface and I upwardly therethrough, and then through another right angle turn out through the discharge opening 28. The principle applied here is based on two physical facts: First, that when a gas or liquid movng within a given space under a certain pressure at a given velocity enters a space of greater area, its velocity is reduced; and the energy released becomes pressure which is exerted equally on all surfaces f the space. Hence, at any orifice equal in size to the interior orifice, the air or liquid may be delivered at the same velocity with which it entered the larger space without loss of energy due to friction. Second, because the coefficient of friction by the two surfaces is the ratio of the force required to move one over the other to the total force pressing the two together; the loss and velocity of liquid or gas in,a duct is greatly increased at a sharp turn; hence, by forming an area of pressure rather than velocity at the point of turn, friction, other than at the orifice, is diminished to a negligible factor.

The refrigerant chamber I5 is adapted to receive a quantity of dry-ice, indicated at 29, through an access opening 30 which is sealed by a door 3! locked into place by any suitable means. The refrigerant chamber is thus entirely sealed except for an outlet pipe 32 which may or may not be provided with any suitable valve means for regulating the rate of escapement of the sublimating gas from the dry-ice. The outlet pipe may also be provided with any suitable connection for directing the gas pressure to any suitable means for utilizing the pressure which would otherwise be wasted.

From the foregoing, it will be seen that through the operation of either motor, 9 or III, the fan 6 draws the air from within the space, or compartment, being refrigerated, and forces it into the space 23, through the longitudinal spaces running along both sides, and between the side walls of the cabinet and corresponding walls of the refrigerant chamber, then downwardly into and through the tunnel, then up through the space 25, and out through the discharge opening 28, and out into the space being refrigerated. By this simple and efiicient means, I am able to quickly refrigerate the space. In Figure l, I have shown the discharge opening 28 formed in the end wall of the cabinet; but it is to be understood that it may be formed in either side wall, as illustrated in Figure 7, or in a top or bottom wall of the cabinet, if necessary or desired.

What I claim is:

Portable refrigeration apparatus comprising, a metallic dry-ice chamber the bottom of which is corrugated and the remaining surfaces of which are planar to provide realtively greater and lesser heat absorbing capacities respectively, a casing and partitions between which and the dry-ice chamber are formed a series of sequentially connected ducts adjacent the dry-ice chamber terminating in an inlet orifice to admit air from the refrigerated space to initial contact with the said surfaces other than the bottom of the dry-ice chamber at one end and in an outlet orifice adjacent the bottom of the dry-ice chamber at the other end, a duct mounted to communicate with said outlet orifice extending upwardly within the refrigerated space, power blower means to impel an air current through the ducts from inlet to outlet, and temperature sensitive control means within the refrigerated space to govern the operation of the blower means.

GLENN D. HEISLER. 

